Game Development Reference
In-Depth Information
arise all that often, but it is worth paying attention to. As a case in point, Unity
3.0 supports FBX 2011 files.
You should always have the latest FBX plugin installed, because you can always
export to previous versions for compatibility reasons while also having the latest
release with the newest features and bug fixes.
22.2.7 Animation
It's more ecient to store all your animations in one FBX file along a single timeline
rather than have an FBX file for each animation. If you are using MotionBuilder
to create and save your animations to the FBX file format, you have the option to
store each animation separately using animation takes. Alternatively, you can use
the FBX Converter's Take Manager tool to extract animation takes from FBX files;
i.e., an FBX file containing five animation takes can be separated into five unique
FBX files. Be sure to verify whether or not your target game engine supports the
reading of animation takes in an FBX file before making this decision.
Shape and morpher animation isn't always supported by game engines. In these
cases, use bone deformations instead. When using bone deformations use the bake
option to retain all animation during the FBX Export process. You will end up
with one key per frame; which allows for 100% animation fidelity between host and
destination applications. The bake animation process converts all IK solving to
FK, removing the dependency on the solvers required to represent the animation
data properly. For instance, since only some game engines support HIK, it's safer
to just bake (resample) the animation on the way out. If you are using set driven
keys in Maya, it's a good idea to set at least one key on your drivers so that baking
is done properly.
When using Biped Layers in 3ds Max, you'll want to select the uppermost
layer before exporting to FBX. If the uppermost layer is selected, all active layers
underneath are considered. The bake animation option must be active in order to
evaluate all layers. Alternatively, you can also simply collapse all Biped animation
layers in 3ds Max before exporting to FBX.
22.3 Extracting the Information from the .fbx File
The .fbx file is used as a common currency between a variety of content creation
tools. To the artist using these tools, the concern is of compatibility, options,
and availability in the tool of choice. This section discusses how to extract the
information from the .fbx file so that it can be used to add rich content to your
game.
There are a number of commercially available game development tools that
provide FBX import. The main way for a game developer to get access to the data
contained within an FBX file is via the FBX-SDK. The FBX-SDK is available free
from
www.autodesk.com/fbx
.
ThissitecontainstheSDKaswellasotherutilities:
